This invention relates to a novel method for preserving or maintaining the softness of dried fruit under storage conditions, wherein the fruit is either stored in isolation or in combination with a relatively dry food product such as ready-to-eat cereal breakfast foods. More specifically, the present invention relates to an improvement over the method described in the Jobin U.S. Pat. No. 3,453,118, said patent being incorporated herein by reference.
Fresh raisins, even when sealed in waxed paper and foil within paperboard containers, progressively lose their softness and become hard, presumably because of moisture losses and chemical changes. The loss of softness or tenderness becomes more pronounced when the raisins are similarly packaged with dry cereal products, such as bran or corn flakes that have a low moisture content relative to the raisins. In order to prevent loss of moisture from the raisins to the cereal, it has been previously necessary to increase the moisture content of the cereal prior to packaging with the raisins. The addition of moisture to the cereal, however, causes a substantial loss of crispness, which is undesirable in many products.
The method of the aforesaid Jobin patent sought to improve softness retention in raisins by subjecting them to the treatment of dipping in a weak acid bath maintained at about 110.degree. F., followed by washing and drying. Although this method produces beneficial results, it would be desirable to provide a means for extending the shelf life of raisins for even greater periods of time.